Emerson instruction manual 396P and 396PVP ORP Sensors, Start-Up & Calibration

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Section 4: Start-Up & Calibration

396P + 396PVP Sensors Instruction Manual

August 2013

LIQ_MAN_396P_396PVP

 

 

2.Measure and record the pH of the process solution sample with another temperature compen- sated, calibrated pH instrument. For best results, standardization should be performed at the process temperature.

3.Adjust the analyzer/transmitter value to the standardized value.

4.2396P and 396PVP ORP Sensors

4.2.1Sensor preparation

Most industrial applications have a number of ORP reactions occurring in sequence or simultane- ously. There can be several components that are oxidized or reduced by the reagents that are used. Theoretically, the ORP potential is absolute because it is the result of the oxidation-reduc- tion equilibrium. However, the actual measured potential is dependent on many factors, including the condition of the surface of the ORP platinum electrode. Therefore, the sensor should be allowed 1-2 hours to become “conditioned” to the stream when first set-up or after being cleaned.

4.2.2ORP Calibration

1.Make a temporary electrical connection between the sensor and the instrument.

2.Obtain an ORP standard solution, or a standard solution can also be made quite simply by adding a few crystals of quinhydrone to either pH 4 or pH 7 buffer. Quinhydrone is only slightly soluble therefore a few crystals will be required. (Refer to Section 4.3. for an alternate ORP standard solution).

3.Immerse the sensor in the standard solution. Allow 1-2 minutes for the ORP sensor to stabilize.

4.Adjust the standardize control of the instrument to the solution value shown in Table 5-1 (below) or on the label of the standard solution. The resulting potentials, measured with a clean platinum electrode and saturated KCl/AgCl reference electrode, should be within ±20 millivolts of the value. Solution temperature must be noted to ensure accurate interpretation of results. The ORP value of saturated quinhydrone solution is not stable over long periods of time. Therefore, these standards should be made up fresh each time they are used.

5.Remove the sensor from the buffer, rinse and install in the process.

TABLE 4-1. ORP of Saturated Quinhydrone Solution (In Millivolts)

 

pH 4 Solution

pH 7 Solution

Temp °C

20

25

30

20

25

30

Millivolt Potential

268

264

260

94

87

80

36

Start-Up and Calibration

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Contents TUpH Combination pH/ORP Sensors This page left blank intentionally Essential Instructions About This Document Contents Table of Contents Description and Specifications Features and ApplicationsDescription and Specifications Specifications General Available pH Accuglass Types Gplr hemi or flat glassOrdering Information Percent LinearityExamples of all sensing tip offerings Accessories Extension Cables required when using a remote junction boxInstallation Unpacking and InspectionMounting Installation Flow Through and Insertion MountingFlow-Through Tee with Adapter PN 40396P02 40396P03 Spray Wash Assembly PN Wiring GeneralWiring Wiring for 396P-01 Gray CableWiring for 396PVP Gray Cable and 54e pH/ORP Wiring for 396PVP 11. Wiring for Dual 396P-02 13. Wiring for 396P-01 Gray Cable and 1056/56 17. Wiring for 396PVP Gray Cable 20. Wiring for 396P-01 Gray Cable 3Wiring 27. Wiring for 396P-01 Blue Cable 29. Wiring for 396P-02 Blue Cable 31. Wiring for 396PVP Blue Cable 33. Wiring for 396P-01 Gray Cable and 5081-P-HT 37. Wiring for 396PVP Gray Cable and 5081-P-HT 41. Wiring for 396P-01 Gray Cable 43. Wiring for 396P-02 Gray Cable 45. Wiring for 396PVP Gray Cable 47. Wiring for 396P-01 Gray Cable and Xmt 51. Wiring for 396PVP Gray Cable and Xmt Wiring Wiring This page left blank intentionally Start-Up and Calibration 396P and 396PVP pH Sensors396P and 396PVP ORP Sensors Start-Up & CalibrationGeneral Information MaintenanceAutomatic Temperature Compensator 396P & 396PVP pH SensorsMaintenance 396P and 396PVP ORPCleaning Platinum Electrode This page left blank intentionally Diagnostics and Troubleshooting Troubleshooting with Advanced DiagnosticsTroubleshooting without Advanced Diagnostics Diagnostics & TroubleshootingDescription Diagnostics & Troubleshooting Warranty This page left blank intentionally Warranty Repair Non-Warranty RepairReturn of Material Emerson Process Management